It does appear that you have a bent axle...you mention c-clip; is it a c-clip rearend or does it have a c-clip eliminator? To check for the bent axle, pull the caliper and rotor off and use a dial gauge to measure radial and face runout directly on axle flange. Another fairly simple way to double check would be to switch axles from side to side to see if the wobble follows the axle.

If the axle is indeed bent, I would replace it as it will generate vibration which apart from being annoying will likely affect the axle seal and/or bearings before too long...tire won't like it either. Lots of replacement options at your favorite mail order racing supply or one of the forum suppliers like Forte's.

Dave